Technologies ARL research scientists are investigating, developing and testing will, some day improve military and commercial airline maintenance programs by detecting, early on, failing parts and systems. In Part 2 of ARL's special series on condition-based maintenance, our cameras travel with Dy Le, chief of ARL's mechanics division within the Vehicle Technology Directorate, to Lakehurst, N.J., to understand the Health and Usage Monitoring System, or HUMS technology, which is essentially the "HUB" of the operation. ARL is developing a number of embedded technologies within the HUMS as part of an ongoing collaborative effort with the Federal Aviation Administration.